Key for organs, pianos, &amp;c.



G. L. CHENEY., FOR ORGANS PIANO y l AAAAAAAAAAAAAAAAAAAAAAAAAA 8.

927,945. Patented Ju1y13, 1909.

. aff 15j. ,a J/ \i UNITED sTATEs PATENT oEEicE.

GEORGE L. CHENEY, OF ESSEX, CONNECTICUT, ASSIGNOR TO PRATT, READ &COMPANY, OF DEEP RIVER, CONNECTICUT, A CORPORATION OF CONNECTICUT.

KEY FOR ORGANS, PIANOS, 85e.

Specification of Letters Patent.

Patented July 13, 1909.

Application led August 21, 1908. Serial No. 449,659.

.particularly to the construction of the mortise of the key into which aguide pin, such as the front guide pin, projects.

The guide pin should it snugly in the mortise, but not bind therein. Oneither side of the mouth or opening to the mortise a piece of bushing orfelt is placed, and the pin projects upward between these bushings intothe mortise. The pin should not rub or bear against the sides of themortise except at the bushing. Uien the key is new the bushing isusually sutlicient to hold the upper end of the guide pin away from theside walls of the mortise, but when the bushing is worn the pin is aptto bind or rub against the side of the mortise, if the mortise is of thesame width throughout as its opening or mouth. Again, a workmanregulating piano and organ keys sometimes finds the keys bind on theguide pin, and therefore wishes to enlarge or widen the hushed part ofthe front mortise which engages closely with the guide pin. The commonway to do this is to pinch each side of the bushed part of the mortisewith pliers, or to drive in a wedge. Not only is this hard to do whenthe whole mortise is of the same interior width, butl it is likely tobring the guide pin, after the bushing is pressed into the wood, incontact with the wood on the side of the morn tise, in beyond thebushing, so that it will scrape on the wood. Consequently, the mortisehas been made wider above the mouth or opening in the bottom of the keythan at the mouth, so that while at the mouth the guide pin will titsnugly its upper end cannot rub or bear on the side walls of themortise. A serious diliiculty has, however, eX- isted in theconstruction of such a mortise because the portion within the key iswider than the opening or inlet to it on the under side orbottom of thekey. Hence it has been customary to form the mortise from the top of thekey before the ivory or celluloid is laid on it, by boring or cutting itdownward of the desired width and then making a narrower continuationextending entirely through the .key to the bottom or under side. The topwas then closed up by inserting a strip or plug of wood, or othersuitable substance, and the narrow opening in the bottom of the keyremained to form the mouth or inlet to the wider mortise above. Theivory or Celluloid was finally placed on the key over the strip or plugof wood. But in inortises formed thus the covering strip or plug of woodwas liable to warp or shrink. rlhis in turn affected the thin layer ofivory or Celluloid above it. Ihe surface of the key became irregular andit was often necessary to plane or smooth the ivory over the coveringstrip or plug. To obviate the necessity of any such covering strip orpiece of wood, in the present invention the mortise is made from thebottom and instead of extending it entirely through the key, itterminates within the key, so that the inner or upper end is closed, notby a separate strip or piece, but by an integral portion of the key. Atthe same time the inner or upper end is wider than the mouth of themortise, so that all the advantages of the former mortise are retainedwithout the concomitant disadvantages.

Referring to the drawings, Figure l represents a vertical longitudinalcentral section through a key embodying the invention. Fig. 2, a bottomview of the outer end of the key, Fig. 3, a transverse vertical sectionthrough the key and mortise,and Fig. 4, a.

similar view with the bushing removed.

In all figures, similar letters of reference represent like parts.

Referring to the drawings for a more particular description, the partdesignated by the letter A represents the front rail of the key board,and B the front guide pin mounted thereon in usual manner.

C designates a key, and D the ivory, celluloid, or similar substance,laid upon it. Within the front end of the key C is a mortise E, which,as shown more particularly in Fig. 4f, has a comparatively narrowopening or mouth F in the bottom of the key, and a wider socket ormortise Gr above. The mortise Gr does not extend entirely through thekey, for its upper end is closed by an integral portion of the key C.The mortise er socket G is considerably wider than the opening F, asshown more particularly in Fig. l, so that while the guide pin B litsnicely Within the opening (Fig. its upper end does not bear or rub onthe side walls of the mort-ise. The mortise is made so that it is aboutone sixteenth of an inch wider in diameter than the opening F.

0n either side of the narrow opening or mouth F is a strip orl bushing Hwhich constricts the mouth or opening, so that the inner portion ol themortise or socket G is not only some one sixteenth of an inch wider thanthe opening' or mouth before the bushing is in place, as shown in Fig.l, but is perhaps an eighth of an inch wider than the opening or mouthafter the bushing is inserted (F ig. rllhus to lorm the mortise from thebottom, so that the opening is narrower than the inner part of themortise or socket above it, a tool may be used having a head wider atleast in one direction than the shank. After the opening is made, arelative movement between the key and tool is given, so that the widerhead or portion of the head will sweep out the mortise laterally abovethe opening to a distance beyond the width of the opening. For example,the shank of the tool may be of a diameter less than the width of theopening. lVhile the tool is rapidly revolving a relative lateralmovement between the key and tool is'imparted, the shank will beconfined in its movement by the sides oli' the opening, but the widerhead will sweep out a socket or mortise somewhat wider than the opening.By thus forming the wider or enlarged mortise trom the bottom of the keyand closing the upper end by an integral part of the key, the necessityof the separate covering strip or piece ol" wood is obviated. Thereforethere is no piece to become warped or to shrink, and so to atleet theivory above. Furthermore, in

l l l the present invention, as only a narrow projecting part of themortise is bushed and engages the guide pin, this can readily be com`pressed by a workman when desired, while the guide pin is still held ata safe distance from the wood on the side of the enlarged inner portionot the mortise.

Having now described my invention, what l claim and desire to secure byLetters Patent, is

l. A key' for an organ, piano or similar instrument having near itslront end a mortise for the reception oit the lront guide pin lormed ina portion ot the key having unbroken and imperlbrate top, side and endsurfaces, and a slot in the bottom ot the key communicating with themortise and ot a width less than the mortise, substantially asdescribed.

2. A key ttor an organ, piano or similar i instrument having near itsfront end a inortise for the reception oli the liront guide-pin formedin a portion o'l the key having unbroken and imperliorate top, side andend surfaces, a slot in the bottom el' the key communieal'ing with themortise and of width less than the mortise, and a bushing on the sidewalls of the slot, substantially as described.

3. A key for an organ, piano or similar instrument having the liront endol its body part formed of a single piece of material and provided witha mortise, a slot for receiving a guide pin leading from the mortisethrough the under side of the body, said slot being of a width less thanthat of the mortise, substantially as described.

In witness wheii'eot l have hereunto set my hand on the day ot July,i908.

GEO. L. CHENEY.

Witnesses lll. lll. lvlon'roN, Giro. A.. lllomrwoon.

